A rare Archaic Period campsite has been discovered along the Minnesota River (USA). Artefacts were found 3 to 4 metres below the ground in an area mostly covered by peat, cat-tails and swamp.
Frank Florin, principal archaeologist at the site, says, "Basically, it's like a time capsule - a very well-preserved record left pretty much intact of where it was deposited. It's exciting to know that you're looking at things as they were 8000 years ago, essentially."
Florin said some of the stones used as tools appear to have come from North Dakota or western Wisconsin, suggesting that the native people traveled some distance in their hunting, or interacted and traded with other groups.
Campsites in the river valley were occupied in a drier period of history, said Minnesota state archaeologist Scott Anfinson. Over the centuries, the climate became wetter, river bluffs eroded and the campsites were covered with silt and soil and filled in as wetlands. That's why ancient sites are so rare.
Craig Johnson, archaeologist for the Minnesota Department of Transportation, said: "We don't have more than about a half a dozen of these archaeological sites from this period that are known in the Minnesota River Valley, so this is pretty significant," he said.
The native people buried their dead high on the bluffs, but camped on the river banks. Florin and crew found artefacts in several spots along a 360-metre stretch. There is at least one buried campsite, and perhaps remnants of others.
"We found evidence for making stone tools, butchering and processing animals, and we found one fire hearth," Florin said. "Since we know so little about this time period, even small campsites are very important for what they tell us about people's diet, what their tools were and how they lived." The crew also unearthed spear-point fragments, hide-scraping tools, and animal remains that included turtles, fish and bison.